Numerous types of apparatus have been used in the past for performing a variety of repair and maintenance functions on railroad roadbeds. Various types of apparatus have been used to perform one or more of the following functions: lifting track from a roadbed; plowing ballast out from under track; depositing fresh ballast beneath track; leveling fresh ballast; removing broken or bad ties; inserting new ties; and realigning track.
One type of prior art apparatus has the capability of lifting track, plowing out ballast material, removing bad ties, and realigning track. This type of apparatus, however, has no provision for carrying a roadbed working tool such as a plow or sled. A separate additional vehicle, such as a flatcar, is required for carrying the plow or sled. A separate handling machine is also required for moving the plow or sled from the flat car to a location adjacent the apparatus. Prior art apparatus of this type has used winch and cable systems to pull a plow beneath the track and apparatus after it has been placed on the ground adjacent lifted track.
Apparatus which lift sections of track travel upon the track on wheeled trucks and utilize hydraulic outriggers to lift desired sections of track. When a section of track is lifted by such an apparatus, the wheels carried by the truck sometimes are lifted out of contact with the rails of the track. After the wheels have left contact with the rails, the rails can become misaligned with the wheels. In the past, bulldozers or jacks have been used to move the track back into alignment with the wheels of the apparatus when the apparatus is lowered. The present invention eliminates the need for using jacks or bulldozers to correct minor misalignments of the track with the wheels.
Plows and sleds of the prior art have used control pads at the rear of the tool to control the cross level at which the tool operates. These control pads have been discrete pads located on either lateral side of the tool with each having a relatively short lateral dimension. These control pads tend to leave small depressions within the roadbed. Such depressions do not promote adequate tie life. One feature of the present invention is directed to overcoming this disadvantage.